- Overview
- Indications of different radiological examination on post mortem.
- Ultrasounds
- X- RAY
- CT scanning
- MRI
- Particularities of post mortem imaging on pediatrics.
overview
Sectional imaging such as radiography should be considered as a complementary tool to autopsy,
along with other examinations,
molecular biology with DNA research, toxicology or pathology. But compared to conventional radio,
sectional imaging is much more "cost effective" for
diagnosis.
CT without injection can identify approximately 15% of lesions that are not observed at autopsy.
Conversely,
half of the autopsy-authenticated lesions are not seen on the scanner.
So these are complementary approaches,
insists F.
Dedouit,
there is no question of replacing autopsy with imaging.
Indications of different radiological examination on post mortem.
+ Ultrasounds :
The ultrasound is indicated in the event of Fetal deaths in utero ((FDIU) or for a Medical Interruptions of pregnancy,
It allows us to realize a multitude of plans, cuts and to adapt them to the anatomical conditions and discovered malformations ,
also it’s More available and cheaper than a MRI but it remains less accurate than the latter
+ X-ray:
Thanks to its accessibility,
standard radiography of the skeleton is the most common technique used on postmortem,
which is an essential complement to the diagnosis with the external ,
internal body examination and laboratory tests.
We can search for bone fractures,
osteosynthesis materials,
foreign bodies and dental equipment .Despite this,
the flat view of the body and the non-visualization of the soft-tissue limit this technique.
+ CT-scanning:
Today,
CT post-mortem have become common practice in many countries around the world for adult patients but also in pediatric practice,
in Switzerland,
for example CT-scans are integrated into forensic institutes.
for this An international nomenclature is being developed under the auspices of an international society (ISFRI),
which has an international journal dedicated to medical imaging and post-mortem imaging.
this technique allows,
without any material destruction (figure2),
the analysis of the whole body.
In the case of pediatric examinations and due to the size of the subject,
volume reconstructions are possible after only one helical acquisition in CT or MRI,
which allow:
- The non-invasive study of difficult anatomical areas to dissect,
which can be documented in a format less "bloody" than classic autopsy photographs (figure 3).
This is particularly useful for the face,
the pelvis and for the cases of serious trauma
- preservation of digital data obtained,
taking into account the necessary requirements in terms of confidentiality in the digital archiving médicale imaging department.
- The possibilities of post-treatment that are now available and can be used quickly at the request of forensic pathologists,
for a suitable demonstration
- multidisciplinary interpretation of images ; Thanks to the "transferability" of data,
which facilitates interpretation away from data from multiple practitioners,
at the same time,
to obtain expert advice in specific areas
- Precise measurements (with a spatial solution up to 0.6 mm) and a perfect location of foreign bodies.
- search for traumatic bone lesions( with the 3D reconstruction (figure 4,5),
visualize the ballistic paths ( figure 6) and gaseous effusions.
However,
its contrast resolution is limited for soft tissues and fluid effusions.
+ MRI :
MRI finds its place in the search for neurological lesions,
as well as the
spinal cord,
in particularly in the cervical region.
The contrast solution
MRI is useful in the characterization of the effusions liquid,
especially
hematological ones ,The disadvantages are artifacts caused by metallic
foreign bodies,
a theoretical risk of secondary displacement of ferromagnetic foreign bodies and the reduced availability of machines.
Particularities of post mortem imaging on pediatrics.
Imaging,
including post-mortem CT scans takes importance in post-mortem investigations,
particularly for intra-hospital deaths,
requiring the family's consent to perform an autopsy.
Since this consent is difficult to obtain in the event of a child's death,
imaging is an alternative way of defining the cause of death,
also its important in the case of maltreatement (figure 7,8,9) and unidentified bodies.
Tuchtan Lucile et al report the case of a newborn found on the stairs by a guardian ,in thi case,
the forensic pathologist must answer the questions of the magistrates : whether the child was born alive,
if he had breathed,
if he was viable,
what would be his estimated age and then obviously if he bears stigma of violence.
In front of all these questions,
a part can be specified before the autopsy thanks in part to the the CT-scan and 3D reconstructions.
These new techniques allow us to perform: fetal biometrics to estimate his age,
view the skeleton in 3D in search of associated malformations and the presence of air in the lungs,
which does not replace the autopsy but it becomes complementary to the preparation for it.
for example In the context of sudden unexpected infant deaths,
according to the recommendations of the "Haute Autorité de Santé "(HAS),
whole body skeletal X-rays and sectional brain imaging (CT or MRI) are performed before the autopsy.